Typical flat-panel displays, such as LC (liquid crystal) and plasma displays, utilize a thin film of electrically-conductive indium-tin-oxide (ITO) that is vacuum deposited on a rigid glass substrate to control various operating functions of the display. That is, during the production of such flat-panel displays, the ITO film is patterned into optically-transparent electrodes using conventional photolithographic techniques. In addition, production of flat-panel displays utilizing photolithographic techniques requires precise and accurate bonding of the electrodes to the driving circuitry of the display, which can be costly. Recently, however, the flat-panel display industry has sought to replace the use of rigid glass substrates with flexible substrates, such as those formed from flexible plastics, while still retaining the use of ITO or other electrically-conductive polymers to form the transparent electrodes using advanced printing and photolithographic techniques.
In addition, while ITO has the desired optical and electrical properties required for many electronics applications, including flat-panel displays and photovoltaic devices for example, ITO is brittle and is easily cracked when the substrate upon which the ITO film is carried is bent or flexed. As such, electronic devices using ITO tend to be fragile and require careful handling and, in some instances, may result in reduced production yields of such electronic devices. In contrast, electrically-conductive polymers, which are an alternative to ITO, have the advantage of being more flexible than ITO and are able to be used in manufacturing processes of electronic devices that utilize printing and photolithographic techniques. However, electrically-conductive polymers have a variety of drawbacks, including reduced electrical conductivity and reduced light transmission as compared to ITO.
Therefore, there is a need for a method of patterning an electrically-conductive film, such as indium-tin-oxide (ITO), into conductive electrodes on a flexible substrate that is low cost. In addition, there is a need for a method of patterning an electrically-conductive film, such as indium-tin-oxide (ITO), into conductive electrodes on a flexible substrate that is compatible with continuous roll-to-roll manufacturing processes. Furthermore, there is also a need for a method of patterning an electrically-conductive film, such as indium-tin-oxide (ITO), into conductive electrodes that are precisely defined. In addition, there is a need for a method of patterning an electrically-conductive film, such as indium-tin-oxide (ITO), on flexible substrates that is simple to execute and that eliminates the need for costly and environmentally-unfriendly materials and solvents.